youngoldbloke;928702][quote name= said:
So does that mean you can judge the quality of a bike purly just by looking at the rear mech?
Yes, to some extent, probably. For example, it would be unlikely to be all that bad if the rear mech was Campag Record.
Edit: - to be serious - (for new bikes) the quality of the components used is going to be reflected in the price, and obviously you would expect to find higher end kit on more expensive bikes - but if one £600 bike has Sora, and another 105, it is worth trying to find out why, as initially the 105 equipped might appear to be the better buy. Of course there are other things to consider - frame, carbon forks (or not), wheels, chainset etc, etc. Also beware of the bike labelled "xxxxx 105", (or the "xxxxx Veloce") when only the rear changer is actually 105, (or Veloce), and not the rest of the groupset, which is from a lesser range, or not the same make at all.[/QUOTE]
I'll agree with this but also if you're looking at a mid-range model for that line of bikes you may want to check out of the top-end bike uses the same frame or not. There seems to be 2 distinct ways used to spec a mid-range bike. One is to use the high-end frame & lower spec components, the other is to use a lower spec frame but higher spec components. Remember that frames last a long time compared to components like rear cassettes, chainrings, etc.
For that reason when I was getting my road bike I picked up the one with the lowest spec components on it. The bike I chose had by far the best frame & much better wheels than the competition making it lighter, stiffer & easier to ride. Over time almost everything has been replaced except the frame.